Cone-bearing branchlet and seed cones [Liu Chunrong, redrawn by Li Aili] (Fu et al. 1999). 4: Cone-bearing branchlet with leaves and seed cones; 5: Branchlet with leaves; 6: Seed [Li Aili] (Fu et al. 1999). Distribution map (USGS 1999. |
Thuja occidentalis Linnaeus 1753Common NamesNorthern white-cedar, thuier cèdre, cèdre-thuya occidental (Chambers 1993), eastern whitecedar, American or eastern arborvitae. Taxonomic notesDescriptionTrees to 15(38) m tall and 90(180) cm dbh, "stunted or prostrate in harsh environments; trunk sometimes divided into 2-3 secondary stems, often reproducing by layering or forming erect, rooted branches from fallen trunks; crown conical. Bark reddish brown or grayish brown, 6-9 mm thick, fibrous, fissured. Leaves of branchlets (1.5)3-5 mm, acute, dull yellowish green on both surfaces of branchlets. Pollen cones 1-2 mm, reddish. Seed cones ellipsoid, (6)9-14 mm, brown; fertile scales usually 2 pairs, each minutely mucronate. Seeds ca. 8 per cone, 4-7 mm (including wings), reddish brown. 2n = 22" (Chambers 1993). RangeCanada: Manitoba, Ontario, Québec; Prince Edward Island, New Brunswick, Nova Scotia; USA: Minnesota, Michigan, Wisconsin, Illinois, Indiana, Ohio, Kentucky, Tennessee, North Carolina, Virginia, West Virginia, Maryland, Pennsylvania, New York, Connecticut, Massachusetts, Vermont, New Hampshire, Maine; at 0-900 m elevation on mostly calcareous substrates, neutral to basic swamps, shores of lakes and rivers, uplands, cliffs, and talus. Isolated stands occur north and east of its general range in Canada (to 51° 31' N latitude in Ontario, 50° N in Quebec). In the United States south of the Great Lakes and in southern New England, it occurs locally in scattered stands and is rare or extirpated at numerous former sites. In some areas, heavy winter browsing by deer greatly reduces reproductive success through elimination of seedlings or saplings (Chambers 1993). See also Thompson et al. (1999). Big TreeDiameter 175 cm, height 34 m, crown spread 13 m, located in Leelanau County, MI (American Forests 1996). Oldest"The oldest living cedar that we have lives on a cliff face and it germinated in 952 A.D. (i.e. 1051 years old). This was determined from a cross-dated tree-ring count back to 1039 A.D. plus an estimated 87 years lost from the pith area. The oldest dead white cedar I've found had a tree-ring count of 1,653 years. This is a pith date from the base. Another white cedar with a ring count of 1,567 years was estimated to be missing 323 rings from its base, thus an estimated age of 1,890 years" (Kelly and Larson 1997, and P.E. Kelly e-mail 15-Nov-2002). DendrochronologyBesides the work by Kelly and Larson (1997), a variety of other studies are indexed on the Bibliography of Dendrochronology. Ethnobotany"Thuja occidentalis is widely utilized in ornamental silviculture and has more than 120 named cultivars. It was probably the first North American tree introduced into Europe (ca. 1566). It is an important timber tree; the wood is used for applications requiring decay resistance" (Chambers 1993). ObservationsRemarksCitationsKelly, P.E. and D.W. Larson. 1997. Effects of rock climbing on populations of presettlement eastern white cedar (Thuja occidentalis) on cliffs of the Niagara Escarpment, Canada. Conservation Biology 11(5): 1125-1132. See Alsoback | Thuja | Cupressaceae | home This page is from the Gymnosperm Database
|